Mahabharatha is not fiction. It is based on facts. So, too is Ramayana. Both of them have fiction, but they are not entirely fiction. They are based on facts. They are called "itihaasa", meaning history.
Both of them date back to more than 5000 years. They were not "scheduled tribes" as you say.
You said we are "aryans". The Aryan-Dravidian theory is pure trash. It is a theory propounded by Britishers and Western historians to keep India divided. It is part of their divide and rule policy.
Our ancient culture did not teach untouchability and sati. These derogatory practices have came up in the recent history (less than 1000 years).
When Muslims invaded India, the Rajput wives burnt themselves to escape from the Muslim rulers. That is how sati became a common practice. Prior to that, women did not practise sati.
